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    <script>
        let set = new Set();
        set.add(1);
        set.add('1');
        console.log(set.size); //2


        let set1 = new Set([7, 2, 8, 3, 35, 31]);
        set1.forEach(function(value) {
            console.log(`${value}`);
            //console.log(key);
        })
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